The present invention relates to a control system for identifying a console device which issues command data and a console device which receives message data in an information processing system having a plurality of console devices for controlling an operation of a computer, and more particularly to a control method, processing method and processing system suitable in function and use when history of issuance of command data and history of display output of message data for each console device are to be obtained.
The term console device used herein means a device which effects communication between an operator and a computer in order to control the operation of the computer and it is different from a terminal device which merely inputs or receives data.
As an application field of a computer system or an information processing system expands, a configuration of the information processing system (which is hereinafter also referred to as the computer system) becomes complex, and an improvement of reliability of the computer system is an important task to be achieved. As an approach to improve the reliability of the computer system, a control system which has two console devices, one for current use and the other for spare, for controlling the operation of the computer system and switches the current use console device to the spare console device is disclosed in JP-A-59-14054. In the control system disclosed in JP-A-59-14054, the current use console device (service processor SUP) and the spare console device are provided, and while the current use console device is in operation, an inhibit signal (IH signal) from the current use console device to the spare console device is set to "1" to logically disconnect a data bus of the spare console device. When switching is made from the current use console device to the spare, the IH signal is set to "0" to logically switch the data bus. In this manner, the switching from the current use to the spare is made instantly.
The prior art technique disclosed in JP-A-59-14054 relates to a control system in which the switching to the single console device provided as the spare is made instantly when an obstacle occurs in the currently used single console device (which can control the computer). In the prior art system, only one of the current use and spare console devices may be used and a plurality of console devices cannot be effectively used.
On the other hand, there has been the following desire on the part of users. As the application field of the computer system expands, the configuration of the computer system becomes complex and the improvement in the operability and reliability is essential. One specific approach to improve the operability and reliability of the computer system is to prepare a plurality of console devices to control the operation of the computer system in such a manner that any console device may issue a data stream of command data for controlling the system. By operating the plurality of console devices simultaneously, it is possible to
1) control the computer system by other console device even if a main console device steps to operate by an obstacle, and PA1 2) control the computer system from geographically distributed locations.
Thus, the reliability of the computer system, particularly, anti-obstacle property for the obstacle of the console device is enhanced. The operability of the computer system is also improved because operators of the computer system may issue commands to the computer system from different locations.
On the other hand, when a plurality of console devices are connected to the computer system, a factor to lower the reliability of the overall computer system, specifically, a factor to induce the halt of the operation of the computer system due to misoperation, increases. Namely, while the anti-obstacle property of the console device is enhanced and the operability is improved, the factor of misoperation of the computer system also increases. Whether the computer operator is an expert or an unexperienced person, there is a risk for inducing the misoperation. In order to centrally control the computer system, it is necessary for a main operator at a main console device to monitor what command has been issued by each of the console devices. It is also necessary to centrally refer history of communication of command data and message data between the console devices and the computer system. Where a plurality of console devices are connected, it is a problem to be solved to provide a support function to immediately locate the console device if it has issued the command data which would induce malfunction. In order to attain the advantage of the multiple console devices, it is necessary to solve those problems.